What is the Damping Term of a Photon?

AI Thread Summary
Photon attenuation is described by the equation I = I_0 * e^(-μz), where μ is the linear attenuation coefficient and z is the distance through the medium. The discussion centers on whether I_0 * e^(-μz) can be considered the damping term for electromagnetic waves associated with photons. It is clarified that if I represents electric or magnetic field intensity, the formula is valid in a homogeneous isotropic medium, but if I refers to intensity, the formula is incorrect. The term "damping" specifically refers to the decrease in the number of photons as they travel through an absorbing medium. Overall, the conversation emphasizes the distinction between intensity and the behavior of photons in a medium.
Watts
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Typically photon attenuation is determined by the equation I = I_0 \cdot e^{ - (\mu \cdot z)}. The variable mu is the linear attenuation coefficient and z is the distance traveled through the substance of transport. Is it safe to say that I_0 \cdot e^{ - (\mu \cdot z)} is the damping term of the electromagnetic wave for the photon? My question is can I write I(z,t) = I_0 \cdot e^{ - (\mu \cdot z)} \cdot e^{i \cdot (k \cdot z - \omega \cdot t)}.
 
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Yes. Carry on.
 
Photon

I can’t carry on any further my question is stated. Am I being unclear?
 
Watts said:
Typically photon attenuation is determined by the equation I = I_0 \cdot e^{ - (\mu \cdot z)}. The variable mu is the linear attenuation coefficient and z is the distance traveled through the substance of transport. Is it safe to say that I_0 \cdot e^{ - (\mu \cdot z)} is the damping term of the electromagnetic wave for the photon? My question is can I write I(z,t) = I_0 \cdot e^{ - (\mu \cdot z)} \cdot e^{i \cdot (k \cdot z - \omega \cdot t)}.


What do you mean on I? If it is electric or magnetic field intensity, your formula is right if that wave travels in direction z, in a homogeneous isotropic medium. If I is the intensity your formula is wrong. Moreover, the wave is damped, not the photon. Damping means that the number of photons decreases with the distance traveled in an absorbing medium.

ehild
 
Intensity

I is the intensity.
 
Watts said:
I is the intensity.

The intensity changes as

I=I_0 e^{-\mu z}

ehild
 
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